Furnace cooling by steam



Dec. 2, 1930.

H. F. EASTER FURNACE COOLING BY STEAM Filed March 9, 1928 conrpzssca A IR FUEL OIL INVENTOR.

M/Z M/ A TTORN E YS.

Patented Dec. 2, 1930 v UNITED STATES PATENT OFFICE nanny rnnnnnro EASTER, or HAYDEN, ARIZONA, Assrenon T AMERICAN SMELTING linnnnrmme cOMrANY, or NEW YORK,'1\T. Y., A CORPORATION OF NEW JERSEY FURNACE COOLING BY STEAM Application filed March. 8., 1928. Serial I10. 260,446.

The invention relates in general to the art of metallurgy and more particularly to a method of and apparatus for cooling a metallurgical furnace and preventing scorification of the brickwork by the contents of the furnace.

Accordingto the invention saturated boiler steam at boiler pressure may be used as the general cooling medium for cooling a metallurgical furnace. The furnace may bea reverberatory furnace andthe steam may be conveniently obtained from the waste heat boiler of the furnace. The furnace may have suitable cooling devices located at different points such ascooling jackets for the side walls or arch, cooled charge holes in the side Walls or in the arch, etc. These cooling devices have conduits associated therewith for the cooling medium and. the live saturated steam is led to these conduits. The cooling of the furnace parts superheats the steam and this superheated steam may be led to any point where it can be used, such as the oil burners used for supplying the heat to the furnace or directly to the inside surfaces of the furnace to protect the brickwork.

According to the invention the saturated steam may also be led directly to the inside of the furnace. Pipes containing this steam may be led through the furnaccwall to the inner face thereof where the steam may form a coating or film on the furnace wall. The

action of this steam willvary with the kind of furnace and the kind of charge. In some cases it may provide an inert film to prevent chemical action between the charge and the brickwork and in other cases the steam may combine with the charge to form strengthening accretions on the brickwork to protect it from thescorifying action of the furnace charge. l

The invention also consists in certain new and original features of construction and combinations, of parts hereinafter set forth and claimed.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and advantages, the mode of its op eration and the manner of its organization may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part thereof, in which q Figure 1 is a diagrammatic view of one form of metallurgical furnace illustrating dlagrammatically how the invention may be applied thereto. Figure 2 is an enlargedsection illustrating the action of'the directly applied steam.

Like reference characters denote like parts in the several figures ofthe drawings.

In the following descriptionand in the claims parts will be identified by specific means for convenience, but they are intended to be as generic in their application to similar parts asthe art will permit.

Referring now to the drawing, a form of reverberatory furnace is shown to illustrate the principle of the invention. It will be understood that the illustration is purely diagrammatic and that the invention may be applied to other kinds of metallurgical furnaces which are capable of utilizing the principles of the invention. 7

The furnace as showncomprises the reverberatory hearth portion 1 having at one end oil burners 2 for supplying the necessary heat. Between the other end of the hearth 1 and the flue 3 a waste heat boiler 4 is provided. p

The furnace roof orarch 5 is shown provided with charge holes 6 which have cooling conduits 7. The furnace is also provided with cooling blocks 8 forming a cooling jacket for the side walls 9. It will be understood that as many cooledcharge openings 6 will be provided in each case as is necessary and they will be placed in the arch or in the side walls as desired and that the cooling blocks 8 may be placed at any point, depending upon the construction of the particular furnace.

In the drawings a saturated steam main 12 is shown leading from the waste heat boiler 4 and conveying live steam at boiler pressure which may be in the neighborhood of150 to 200 pounds.

This steam main 12 leads todift'erent parts of the plant where the steam is needed and is shown provided with branch conduits 13 leading to the various cooling blocks 8 and charge holes 6 for cooling these parts. Leading from the cooling locks and charge holes are branch conduits 14 leading back to another main 15,.which is the superheated steam main. This main 15 may be led to any other part of the plant where superheated stea-m can be used. A branch 16 is shown extending to s the oil burner 2 from both the saturated steam main 12 and the superheated steam main 15. Also connected to the oil burner is a sourceof fuel oil and a source of compressed air.

Connected also to the saturated steam main 12 are branches 1'? leading directly to the interior of the furnace and ending substantially flush with the inner face of the roof These branches may also receive steam from the superheated main 15. It will be seen that these branches 17 may be used to convey either superheated or saturated steam directly inside the furnace to form protective coatings upon the roof or on the side walls of the furnace, depending on the position and number of branch pipes. Valves 18 are provided in the several branches for controlling the steam flow.

In operation it"will be understood that saturated steam, which is conveyed to the cooling blocks and charge openings, is superheated by its cooling action,-and the superheated steam is used to form the protective coating on the inside of the furnace, to improve the action of the oil burners, and for other purposes, if desired.

The steam passing thru the branch pipes 17 which lead directly to the interior of the furnace form protective coatings on inside walls, the actions depending upon the kind of furnace and the material of the charge. In some asesthe steam may act merely as an inert gas to protect the brickwork from sc0rification due to the furnace charge. In other cases the dust or other material of the charge or other contents of the furnace may combine chemically with the steam and'form a precipitate which is deposited on the brickwork forming a strengthening accretion which protects the brickwork from the scorifying action.

Thus it will be seen that a method of cooling and protecting a metallurgical furnace has been provided which inexpensive and eflicient. Metallurgical furnaces are usually provided with waste heat boilers so that steam is easily obtainable. The cooling action of boiler steam. is more efficient than that of water and there is no danger of explosion from accidental leaks. Furthermore, the utilization of steam directly inside of the furnace, forming a coating on the furnace walls, protects the brickwork from scorification and aids materially in increasing the life of the furnace. Also the superheated steam obtained from the cooling action may be used to improve the efliciency of the oil burners.

What is claimed is:

1. The method of protecting the inside wall of ametallurgical furnace from the scorifying action of' the contents of said furnace which comprises forming a coating of steam on said inside wall, without substantially changing the normal operating atmosphere throughout the body of the furnace.

2. The method of protecting the roof of a reverberatory furnace from the fluxing action of the charge which comprises coating the interior of said roof with superheated steam, without substantially changingthe normal operating atmosphere throughout the body of the furnace.

The method of protecting the inside wall of a reverberatory furnace from the attacking action of the charge which comprises coating the interior of said wall with steam, without substantially changing the normal operating atmosphere throughout the body of the furnace.

1. The method of protecting the interior of a wall of a metallurgical furnace from the fluxing action of the contents of said furnace which comprises coating a film of steam on said wall, reacting said steam and part of said conte ts and depositing the compound formed on said wall to form a protecting accretion.

In combination, a source of saturated steam at boiler pressure, a metallurgical furnace having a cooling conduit associated with the wall thereof, means for passing steam from said source thru said conduit to cool said wall and to superheat the steam, and means for passing said superheated steam directly to the interior of said furnace to form a coating on the inner wall thereof.

(3. In combination, a source of saturated steam at boiler pressure, a metallurgical furnace, a cooling conduit in a wall of said furnace, means for passing steam from said source thru said cooling conduit and then directly to the interior of said furnace at the inner surface of the wall thereof.

7. In combination, a source of steam, a metallurgi -.al furnace, a. cooling conduit in a wall of said furnace, and means for passing steam from said source thru said cooling conduit and then directly to the inside of said furnace.

In testimony whereof I have hereunto set my hand.

HENRY FREDERIC EASTER. 

